Simpson Strong-Tie ETB6 Nylon Hole Cleaning Brushes for 1/2" to 3/4" diameter holes are an important part of making sure both epoxy and wedge anchor systems work in the most effective manner. By cleaning the hole after drilling as completely as possible the anchor or epoxy is assured of creating a connection that meets the load requirements.Overall Length: 16" Brush Length: 4" Hole Diameters: 1/2" to 3/4" Additional Simpson Strong-Tie Information If there are any items on the Simpson Strong-Tie Website that you do not see on the DHC Supplies website we will gladly special order them. Most special order Simpson items ship the same or next business day. Call us at 800-323-2999 for pricing and availability. Important: Selecting USPS as a shipping method for any Simpson Strong-Tie product may delay shipping 1-2 days. Additionally, international shipments may also be delayed 1-2 days.Possible Free Shipping! Orders (Continental USA Only) of Simpson Strong-Tie items only that total $1850.00 or more may ship free depending on location, type of business and the type of Simpson products required. Additional products will be charged standard shipping if applicable. Please call 800-323-2999 to see if your order qualifies.